Protein oxidative changes in whole and skim milk after ultraviolet or fluorescent light exposure.

We investigated how protein changes occur, at the primary or higher structural levels, when proteins are exposed to UV or fluorescent (FL) light while in the complex matrix, milk. Whole milk (WM) or skim milk (SM) samples were exposed to FL or UV light from 0 to 24h at 4°C. Protein oxidation was evaluated by the formation of protein carbonyls (PC), dityrosine bond (DiTyr), and changes in molecular weight (protein fragmentation and polymerization). Oxidative changes in AA residues were measured by PC. Dityrosine and N'-formylkynurenine (NFK), a carbonylation derivative of Trp, were measured by fluorometry. Protein carbonyls increased as a function of irradiation time for both WM and SM. The initial rate for PC formation by exposure to FL light (0.25 or 0.27 nmol/h for WM and SM, respectively) was slower than that following exposure to UV light (1.95 or 1.20 nmol/h, respectively). The time course of NFK formation resembled that of PC. After 24h of UV exposure, SM had significantly higher levels of NFK than did WM. In contrast, WM samples irradiated with UV had higher levels of DiTyr than did SM samples, indicating different molecular pathways. The formation of intra- or intermolecular DiTyr bonds could be indicative of changes in the tertiary structure or oligomerization of proteins. The existence of NFK suggests the occurrence of protein fragmentation. Thus, proteolysis and oligomerization were analyzed by sodium dodecyl sulfate-PAGE. After 24h of exposing WM to UV or FL light, all the proteins were affected by both types of light, as evidenced by loss of material in most of the bands. Aggregates were produced only by UV irradiation. Hydrolysis by pepsin and enzyme-induced coagulation by rennet were performed to evaluate altered biological properties of the oxidized proteins. No effect on pepsin digestion or rennet coagulation was found in irradiated SM or WM. The oxidative status of proteins in milk and dairy products is of interest to the dairy industry and consumers. These findings provide knowledge that could be useful in determining the optimal lighting conditions in the dairy industry in general and in cheese making in particular.

DNA: a model compound for solution studies of macromolecules.

Well-defined, monodisperse, homologous series of oligonucleotides and DNA restriction fragments may now be produced and used as models of rigid and semirigid rodlike molecules in solution. Information from optical experiments on these model systems aids in the formulation and testing of theories of macromolecular dynamics in both dilute and concentrated solution.

Shortage of Donors for Intestinal Transplantation in São Paulo, Brazil.

BACKGROUND: The number of deceased organ donors has decreased slightly over the past 4 years. Although the pool of intestinal transplantation candidates is relatively small, donor allocation is challenging because of the inability to maintain the donor in a good condition and the complexities involved in making a suitable weight match between donors and recipients. Our goal was to analyze the epidemiologic profile of potential donors based on the organs offered by the regional Organ Procurement Organization from Hospital das Clinicas-USP (OPO/HC-USP) and attempt to estimate possible matches and program viability. METHODS: We retrospectively analyzed information from the OPO/HC-USP database regarding organs offered over the past 7 years as well as patients listed in our program. Data were collected regarding donor characteristics (eg, sex, age, race, body mass index, blood type, cause of death) and medical care details (eg, intensive care unit stay, use of vasopressor agents and antibiotics). RESULTS: In this time period, there were 18,103 brain death notifications in the state of São Paulo; 5,202 (35%) became viable donors, resulting in 5,201 (99%) effectively used livers and kidneys. Most potential donors were male, in their 40s, white, and had blood type O. Only 3 potential donors from OPO/HC-USP would have reached the established minimum criteria for intestinal donation over these 7 years.

Ring chromosome 5 associated with severe growth retardation as the sole major physical abnormality.

We report on a case of ring chromosome 5 in a 36-month-old girl with severe growth retardation, clinodactyly, mild psychological abnormalities, and normal facial appearance. Endocrine tests showed partial growth hormone deficiency. Cytogenetic investigation failed to demonstrate any apparent microscopic deletion of either short or long arm of chromosome 5 as consequence of ring formation. In 12% of cells examined, the ring was either absent or present in multiple copies. Only 3 previous cases of ring chromosome 5 have been reported in association with short stature of prenatal onset and minor anomalies, without mental retardation.

Skeletal muscle myosin subfragment 1 dimers.

The rate of translational diffusion of skeletal muscle myosin subfragment 1 (S1) was determined from polarized dynamic light scattering autocorrelation measurements. Diffusion rates were expressed in terms of the hydrodynamic radii Rh. At 20 degrees C, in low ionic strength pH 8 solutions, Rh increased from 4.3 nm to 5.7 nm as [S1] was increased from 1.6 to 72 microM. Including MgATP to maintain S1. MgADP. Pi gave equivalent results. When the light scattering data were analyzed, assuming a monomer-dimer equilibrium, a dissociation constant of 83 microM was obtained. Steady state MgATPase activity measurements were made as a function of [ATP] for S1 in the 0.4-7 microM range, and analyzed assuming Michaelis-Menten kinetics. VMAX did not change, but KM increased about tenfold as [S1] was increased over this range. The light scattering and kinetic data were consistent with S1 aggregation at high [S1].

Dynamic light scattering studies of ribonuclease.

Dynamic light scattering has been used to measure the translational diffusion coefficients of bovine pancreatic ribonuclease A as functions of temperature and concentration in the presence of 1 M Guanidine-HCl. Data was collected throughout a temperature range including the folding-unfolding transitions. Evidence of a pretransition "swelling" of the protein was observed. Entropy and enthalpy changes upon unfolding were obtained using a two-state model.

Diagnosis of MODY in the offspring of parents with insulin-dependent and non-insulin-dependent diabetes mellitus.

Maturity Onset Diabetes of the Young (MODY) is an autosomal dominant monogenic form of type 2 diabetes mellitus (DM) representing 5% of youth-onset DM in the Caucasian population. In young adults the disease can be present as either non-insulin dependent or insulin-dependent DM. The diagnosis of this genetic disorder in children and adolescents is rare because of the mild glucose metabolism disorder at this time. We performed a metabolic, autoimmune and genetic study in 40 offspring of young parents affected by insulin-dependent DM (Group A) and in 35 offspring of young parents affected by early-onset non-insulin-dependent DM (Group B). Two children of Group A (5%) were found to be affected by fasting hyperglycemia and carry a GCK gene mutation that in one case was present also in the diabetic father. Eighteen offspring of Group B (51%) were positive for GCK or HNF-1alpha gene mutations present in the affected parents. All but two of these young patients had impaired fasting glucose (IFG) or impaired glucose tolerance (IGT). Eleven of them were younger than 16 years. We conclude that screening for DM in youth should be extended to MODY in young families with both non-insulin-dependent and insulin-dependent DM. The sensitivity of the metabolic tests will precede the genetic diagnosis.

Treatment of dysarthria: a case report.

There is little information available to the speech clinician on management of dysarthria. This article presents the rationale, procedural outline, and results of an approach to communication training for one dysarthic subject in view of suggestions made by Darley et al. (1975).

"Hallervorden-Spatz syndrome--infantile neuroaxonal dystrophy" complex. Case report.

Case report of a 7 1/2-year-old girl considered as being normal until the age of 2 years. From then on she progressed with gait disturbance, mental deterioration, dystonic movements, convulsions and dysarthria. She died of bronchopneumonia one year later. CT scan showed hyperdensity at the putamen, with no signs of cerebral atrophy. Pathological examination disclosed an intense red coloration of the putamen and axonal "spheroids" at electron microscopy.

[Circadian variability of IgE in children: effects of a thymic hormone (thymomodulin)]. / Variabilità circadiana delle IgE nel bambino: effetto di un ormone timico (timomodulina).

Since thymic factor activity can modulate immunoglobulin production, thymomodulin effect on IgE secretion was studied in thirty children (20 atopic and 10 control patients). Before treatment circadian variability of IgE was verified in all the children. Thymomodulin (3 mg/kg/die) was given daily for 30 days in both groups. Disappearance of circadian IgE variability were observed in atopic children, while no change of serum IgE circadian levels occurred in control group. On the basis of our results an improvement of IgE disregulation in atopic children may be postulated.

Ten years' evaluation of potential pancreas donors in São Paulo, Brazil.

BACKGROUND: Pancreas transplantation is a treatment for advanced type 1 diabetes and offers significant improvement in quality of life. Recent advances in surgical techniques and immunosuppression regimes lead to good outcomes. However, despite significant higher rates of multiorgan donors in Brazil, pancreas transplantation seems to have remained stable. This study aimed to investigate the acceptance rate of potential pancreas donors in the past 10 years in São Paulo State. METHODS: We retrospectively evaluated potential pancreas donors characteristics and its acceptance rate in São Paulo State in the past 10 years. We divided this period into 2 eras: 1st era from January 2003 to January 2008; and 2nd era from January 2008 to January 2013. Data were obtained from São Paulo's government official website. RESULTS: During the whole period, 5,005 deceased donors of all ages were available for pancreas transplantation. According to eras, we had 1,588 donors in the 1st and 3,417 in the 2nd era. In the 2nd era, donors >49 years old were significantly more common (P < .001). Blood test abnormalities, donor comorbidities, and high dosage of vasopressors also were significantly higher in the 2nd era. Rate of graft acceptance had a significant decrease in the 2nd era, from 46.4% to 25% (P < .05). CONCLUSIONS: Despite greater organ availability, pancreas transplantations performed in São Paulo State remained stable. Rate of graft acceptance is dramatically lower in more recent years.

Home parenteral nutrition program and referral of potential candidates for intestinal and multivisceral transplantation in a single Brazilian center.

Intestinal failure is a multifaceted condition that may require high-complexity treatment and a multidisciplinary program, including home parenteral nutrition therapy (HPNT) and intestinal transplantation. In this article, we profile a Brazilian single-center experience with 128 cases of HTPN followed for the last 30 years and appraise the referral for potential intestinal and multivisceral transplantation.

Intestinal and multivisceral retransplantation results: literature review.

BACKGROUND: Intestinal/multivisceral transplantation (IT/MVT) is the gold standard treatment for patients with intestinal failure and complications related to total parenteral nutrition, gastrointestinal inoperable indolent tumors, or diffuse portal trombosis. Currently, the reported 1-year patient survival rate is around 80%, similar to other solid organ abdominal transplantations. Unfortunately, the patient survival decreases after the first year with the 5-year rate not close to 70% yet. Acute cellular rejection is the main cause of graft loss. Its early diagnosis may make it possible to improve survival of retransplantations. OBJECTIVE: To analyze the reported results published in the last 5 years by leading transplant centers to evaluate IT/MVT retransplantation results. METHODS: We performed a literature review using PubMed focusing on multivisceral and intestinal retransplantation in articles published between 2006 and 2012. In relation to the first transplantation, we analyzed demographics, imunosuppression, rejection, infection as well as graft and patient survival rates. RESULTS: Two centers reported results on intestinal and multivisceral retransplantations. Mazariegos et al reported their experience with 15 intestinal retransplantations in 14 pediatric recipients. Four patients died from posttransplant lymphoperliferative disease, severe acute cellular rejection, fungal sepsis, or bleeding from a pseudoaneurysm at a mean time of 5.7 months post-transplantation. Total parenteral nutrition was weaned at a median time of 32 days. Abu-Elmaged et al reported 47 cases with a 5-year survival of 47% for all retransplant modalities. Retransplantation with liver-contained visceral allograft achieved a 5-year survival rate of 61% compared with 16% for liver-free visceral grafts. CONCLUSION: Despite those huge improvements, some transplanted patients develop severe acute cellular rejection, culminating in graft loss and retransplantation. Repots on multivisceral and intestinal retransplantation outcomes suggest that it is a viable procedure with appropriate patient survival after primary graft loss.

Intestinal and multivisceral transplantation immunosuppression protocols--literature review.

INTRODUCTION: Currently the most used techniques for small bowel transplant are isolated intestinal transplantation, multivisceral transplantation (MVT), and modified multivisceral transplantation. One important factor is early diagnosis of acute cellular rejection (ACR). In addition, improvements in immunosuppression have recently reduced the number and enhanced treatment of ACR episodes, enabling graft recovery. OBJECTIVE: We analyzed immunosuppression protocols of leading transplantation centers in the last 5 years. METHOD: We reviewed papers published in PubMed from major multivisceral and intestinal transplantation centers from 2006 to 2010 in adult recipients. The 211 adults transplanted in seven centers were divided into three groups according to the immunosuppression protocol used: protocol 1: daclizumab induction with tacrolimus and steroid maintenance; protocol 2: alemtuzumab and tacrolimus; and protocol 3: thymoglobulin and rituximab and tacrolimus. RESULTS: Protocol 2 showed the lowest rate of ACR (34%). Protocols 1 and 3 displayed 54% and 48% ACR rates; respectively. However, protocol 1 patients developed only mild ACR, whereas those in protocols 2 and 3 developed moderate ACR in 26.3% and 11.7%, and severe ACR in 7.9% and 47% of cases, respectively. The infection rate was considerably lower in protocol 3 (7.4%). Protocols 1 and 2 showed infection rates of 62.5% and 52%, respectively. One-year patient survival rates were 70%, 79% and 81%, respectively. Three-year patient survival rates were 62%, 56%, and 78% for protocols 1, 2 and 3, respectively. CONCLUSION: Protocol 2 was the strongest immunosuppressive regimen capable of reducing ACR rates when compared with the other protocols, but the strong effect resulted in high infection rate that impacts 1-year patient survival. Protocol 3 seems to be the best available one balancing ACR and infection rates.

Informe de la CABE-FASEN: Monitoreo de desórdenes por defciencia de iodo (DDI) en la provincia de Santa Fe, Argentina (2007) / CABE-FASEN Report: Screening of Disorders Associated with lodine Defciency in the Province of Santa Fe, Argentina (2007)

Un total de 1.470 alumnos de escolaridad primaria, de ambos sexos, fue estudiado en este monitoreo de bocio endémico en cuatro localidades de la provincia de Santa Fe: Reconquista (n=404) y Villa Ocampo (n=294) ubicadas en el norte de la provincia, y Rufino (n=317) y Venado Tuerto (n=455) ubicadas en el sur provincial. La edad de los escolares osciló entre 6 y 14 años. Se examinó el cuello de todos los escolares; con el fin de aunar criterios con los realizados en otras provincias, se tomó como referencia la palpación de un solo médico (HN). La definición del grado de bocio fue la misma que fuera utilizada en los otros relevamientos. Se determinó la ioduria en muestras casuales de orina emitidas por los niños una vez que fueron palpados (109 de Reconquista, 105 de Villa Ocampo, 113 de Rufino y 139 de Venado Tuerto). Se midió también el contenido de iodo en 337 muestras de sal de consumo hogareño de Reconquista, 227 de Villa Ocampo, 295 de Rufino y 422 de Venado Tuerto (traídas por los niños desde sus viviendas). El examen palpatorio de los niños reveló una prevalencia de bocio del 2,6%, sin diferencias por localidad. Los niveles de ioduria mostraron diferencias entre las localidades del norte y del sur: en Reconquista 238,6±116 µg/L con mediana de 213 µg/L, y en Villa Ocampo 241,6±223,5 µg/L con mediana de 188 µg/L; mientras que en Rufino 544±349 µg/L con mediana de 442 µg/L y en Venado Tuerto 550±375 µg/L con mediana de 418 µg/L (media±DS). Los niveles de iodo en sal fueron similares en toda la provincia, promediando los 35,5 mg/kg. La prevalencia de muestras con concentraciones de iodo <15 mg/kg fueron del 0,3% para Reconquista, del 1,3% en Villa Ocampo, del 3 % en Rufino y del 4 % en Venado Tuerto. Concluimos que en la provincia de Santa Fe no existe endemia bociosa. Los autores declaran no poseer conflictos de interés.

A total of 1,470 primary school students were evaluated to monitor the prevalence of endemic goiter in four cit-ies of Santa Fe province: Reconquista (404) and Villa Ocampo (294) situated in the north, and Rufino (317) and Venado Tuerto (455) situated in the south of the province. Their age ranged from 6 to 14 years. Neck palpation was performed in all students; for the sake of consistency with monitoring performed in other provinces, palpation was performed by only one physician (HN). The goiter grading system was the same used in other surveys. After palpation, urine samples for iodine determination were randomly collected (109 from Reconquista, 105 from Villa Ocampo, 113 from Rufino and 139 from Venado Tuerto). Iodine was also measured in salt samples collected from the children's homes (337 from Reconquista, 227 from Villa Ocampo, 295 from Rufino and 422 from Venado Tuerto). Prevalence of goiter was 2.6 % without differences among cities. Urine iodine levels were significantly different between northern and southern cities: Reconquista had a mean of 238.6 ± 116 µg/L (median 213 µg/L) and Villa Ocampo had a mean of 241.6 ± 223.5 µg/L (median 188 µg/L), while in Rufino the mean was 544 ± 349 µg/L (median 442 µg/L) and in Venado Tuerto it was 550 ± 375 µg/L (median 418 µg/L; mean ± SD). Iodine contents in salt were similar across the province, with a mean of 35.5 mg/kg. Prevalence of salt samples with iodine concentration <15 mg/kg was 0.3 % in Reconquista, 1.3 % in Villa Ocampo, 3 % in Rufino, and 4 % in Venado Tuerto. We conclude that the province of Santa Fe, Argentina, is free from endemic goiter. No financial conflicts of interest exist.

Diffusion and microstructural properties of solutions of charged nanosized proteins: experiment versus theory.

We have reanalyzed our former static small-angle x-ray scattering and photon correlation spectroscopy results on dense solutions of charged spherical apoferritin proteins using theories recently developed for studies of colloids. The static structure factors S(q), and the small-wave-number collective diffusion coefficient D(c) determined from those experiments are interpreted now in terms of a theoretical scheme based on a Derjaguin-Landau-Verwey-Overbeek-type continuum model of charged colloidal spheres. This scheme accounts, in an approximate way, for many-body hydrodynamic interactions. Stokesian dynamics computer simulations of the hydrodynamic function have been performed for the first time for dense charge-stabilized dispersions to assess the accuracy of the theoretical scheme. We show that the continuum model allows for a consistent description of all experimental results, and that the effective particle charge is dependent upon the protein concentration relative to the added salt concentration. In addition, we discuss the consequences of small ions dynamics for the collective protein diffusion within the framework of the coupled-mode theory.

Milk fat content measurement by a simple UV spectrophotometric method: an alternative screening method.

We developed a simple microtechnique to measure lipids in milk by UV spectrophotometry. This technique is based upon the property of fatty acids to absorb UV light proportional to their concentration. Samples of powdered or fluid milk (30 or 60 muL) were added to 3 mL of analytic grade ethanol and stored at -20 degrees C for at least 1 h. This procedure precipitates proteins and hydrophobic peptides that interfere with UV measurement. Sample absorbances are then measured at 208 nm in an UV-Vis spectrophotometer. This technique correlated very well against Milko-Scan, a device that measures milk fat by IR spectroscopy, with an r(2) >0.982. Accuracy and precision, evaluated by recovery and replicate assays, are also very acceptable. This method is suitable as a fast, cost-effective alternative screening method to estimate milk fat content in small samples without prior lipid extraction.

Monitoreo de DDI en la provincia de La Rioja (2006) / Monitoring of DDI in the province of La Rioja (2006)

Un total de 712 alumnos de escolaridad primaria, de ambos sexos, fue estudiado en este monitoreo de bocio endémico en dos localidades de la provincia de La Rioja: Ciudad de La Rioja (442 niños) y Chilecito (270 niños). La edad de los escolares osciló entre 5 y 16 años. La palpación tiroidea fue hecha por el conjunto de los médicos participantes. Sin embargo, con la finalidad de aunar criterios con lo realizado previamente (1-24), se tomó como única referencia la palpación de H.N., que se llevó a cabo en la totalidad de los niños estudiados. La definición del grado de bocio fue similar a la utilizada en los otros relevamientos (1). Se determinó la yoduria en muestras casuales de orina emitidas por los niños una vez que fueron palpados (125 de La Rioja y 128 de Chilecito). Se recolectaron 251 muestras de sal de consumo hogareño de La Rioja y 141 de Chilecito, para medir su contenido en yodo. El examen palpatorio de los niños reveló la existencia de bocio grado 1 solamente. La prevalencia de bocio encontrada fue de 1,8% en La Rioja y de 2,6% en Chilecito. Los niveles de yoduria alcanzaron, en La Rioja, una media de 226 ± 181 (DS) μg/L y una mediana de 186μg/L, al tiempo que en Chilecito la media fue de 217 ± 161μg/L y la mediana de 185μg/L. El contenido de yodo de las sales, que aportaron los alumnos desde sus hogares, fue adecuado para casi todas las marcas. De esta manera, observamos que en la ciudad de La Rioja el promedio de yodo en la sal, tomada en conjunto, fue de 33,1 ± 12,5 mg/Kg, mientras que para Chilecito fue de 28,1 ± 8,2 mg/Kg. Al analizar las concentraciones de yodo <15mg/Kg, observamos que fue del 10,7% en La Rioja y del 9,5% en Chilecito. Teniendo en cuenta la línea de corte del 10% que fija el ICCIDD (25) como valor óptimo, podemos observar que la situación fue prácticamente satisfactoria en ambas poblaciones. Concluímos que en estas dos poblaciones de la provincia de La Rioja no existe, actualmente, bocio endémico por deficiencia de yodo. Estos resultados indican que la profilaxis con sal yodada fue óptima en esta provincia, dado que en el pasado solía ser una típica zona yodo-deficiente con un muy alto porcentaje de bocio endémico.

Solution dimensions of the gramicidin dimer by dynamic light scattering.

Gramicidin is thought to form dimeric helical rods in alcohol solutions. In addition, there is evidence that the rod dimensions change upon addition of potassium ions. The present work reports values for the translational and rotational diffusion coefficients of gramicidin in methanol and 95% ethanol and in these same solvents with added KSCN. Solution dimensions are calculated from the diffusion coefficients. The results suggest that gramicidin exists primarily as dimers in these solutions and that the gramicidin rod does indeed become shorter upon addition of potassium ion. These results are consistent with those obtained from X-ray studies on single crystals grown from alcohol solutions.